Stamping device.



W. J. GROTENHUIS.

' STAMPING DEVIUEL APPLICATION FILED MAY 11, 1911.

1,022,076, Patented Apr.2, 1912.

W2 171655.95. fnvenlor:

COLUMBIA PLANLXIRAPII KL-WASHINGTON D c UNITE STATES PAN OFFICE.

WILLIAM J. GROTENHUIS, OF CHICAGO, ILLINOIS, ASSIGNOR OF ONE-HALF TO PHILIP A. SALISBURY, OF CHICAGO, ILLINOIS.

STAMPING DEVICE.

To all whom it may concern.

Be it known that I, VTLLIAM J. Gno'rmv HUIS, a citizen of the United States of America, and resident of Chicago, Cook county, Illinois, have invented a certain new and useful Improvei'nent in Stamping Devices, of which the following is a specification.

My invention relates to rubber stamps of the kind in which one or more endless rubber bands are provided with raised letters or numerals for making the impression. These bands travel under a bridge which forms a backing for the rubber portions which are required to make the impression at any particular time. hen another impression is desired the bands are moved along until other portions thereof are brought into position below and against the bridge. \Vith the ordinary construction, however, there is always some tendency for the bands to creep on the bridge, and to thereby impair the accuracy of the impression.

The object of my invention is, therefore, to provide an improved arrangement for preventing creeping of the bands on the bridge, by the use of depressions in the backs of the bands, which depressions are of such character that the back or inside of each band has a practically continuous flat wearing surface, and to thereby render the rubber stamp more reliable than heretofore, as will hereafter more fully appear.

In the accompanying drawingsFigure 1 is a side elevation of a rubber stamp embodying the principles of my invention. Fig. 2 is a vertical section of the same. Fig. 3 is a side elevation of the bridge of my improved-rubber stamp. Fig. 4; is a perspective of the said bridge, showing one end thereof in crosssection. Fig. 5 is a perspective of portions of the rubber bands which travel across the bridge, on the under side thereof, and which carry the raised letters or numerals for making the impression.

As thus illustrated, my invention comprises a body A having a handle a at its upper end and a shaft 0; extending horizontally from one side thereof to the other below said handle. On this shaft are the rolls a which have the thumb-wheels a by which they are turned to properly adjust the stamp. At its lower end the frame or body A has a horizontal member B called a Specification 01 Letters Patent.

Application filed May 11, 1911.

Patented Apr. 2, 1912.

Serial No. 626,476.

bridge. This bridge is of sheet metal, being trough-like in shape, and has its face formed with a longitudinal rib Z) extending centrally thereof. The rubber bands C are of the usual character, except that they are thicker than usual and provided on their backs with transverse notches or grooves c which engage the rib Z) to hold the bands in proper position. These bands are, of course, elastic in character, and yield enough to permit the thick portions between the notches c to ride over the rub I) when it is desired to adjust the stamp for a different nnpression.

The letters or numerals, it will be understood, are raised on the outer surfaces of the bands, in the usual and well-known manner. The notches c are so positioned and spaced apart that each notch is directly back of a letter or numeral, or of a group of letters or numerals, as shown, whereby the engagement of a notch c with the rib Z) insures accurate positioning of the bands. This also prevents creeping of the bands, as the strength and resiliency of the bands are such that only forcible rotation of the wheels a can move the notches 0 out of engagement with the rib 7). The notches 0 are, of course, adapted to contract while passing around the roll o owing to the flexing of the band at this point. Thus the accuracy of the device is insured, and a heretofore serious dilliculty entirely remedied.

The advantage of the foregoing construction is that each band has its back or inside formed with practically a continuous flat wearing surface which reduces wear and prevents the belts or bands from rapidly deteriorating in use. In other words, the depressions c are of minimum size, while the portions between, which are subject to wear or abrasion, are flat and of maximum size or area. Thus, as stated, the inside of the belt is left practically flat, and in addition the maximum thickness of the belt is of greater area; and in this way the belts will last longer. Moreover, the notches or. depressions facilitate the flexing of the bands around the rolls.

It is the object of my invention to hold the belt or band in place without using something that will readily wear away. This I do by putting the small projection on the bridge, which is of metal and thus not calculated to wear away, and by using the rubber, which is soft and comparatively perishable, in such form that it has nothing to wear off. By a small projection I mean one which is relatively small, as also the depressions in the band or belt.

What I claim as my invention is:

In a rubber stamp, a band having its face provided with means for making impressions, a stationary bridge across the flat face of which the band travels to change the impression, and rotary means for operating the band, the said bridge having a small projection on the face thereof, and said band having a series of relatively small and separated positioning depressions on the back thereof, with substantial flat surfaces between said depressions, whereby the back of each band has a practically continuous flat wearing surface, said fiat surfaces adapted to engage the fiat face of said bridge, said projection adapted to engage said depressions, said band being thickened to accommodate said depressions in the form of transverse notches, said notches facilitating the flexing of the band around said rotary means, and said projection being in the form of a rib extending longitudinally of the bridge at a point midway between the sides thereof, said notches adapted to contract while the band is passing around said rotary means, as set forth.

Signed by me at Chicago, Illinois, this 5th day of May, 1911.

WILLIAM J. GROTENHUIS.

WVitnesses R. KEARNs, S. LEWIS.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents. Washington, D. C. 

